1. Field of the Invention
The invention relates to a drive train for a hybrid vehicle, comprising a parallel-hybrid partial train and a serial-hybrid partial train.
2. Description of the Related Art
Drive trains for hybrid vehicles are known in various embodiments. For example, a parallel-hybrid has an internal combustion engine and an electric machine arranged in a way to apply power or torque individually or communally to the drive train to drive the hybrid vehicle. Thus, the electric machine can assist the internal combustion engine. Furthermore, a serial-hybrid has an internal combustion engine that drives an electric machine, which is operated as a generator. Electric current generated in this manner is fed to an electric accumulator, such as a battery, and/or is used to supply an electric machine that is operated as a motor. This permits consumption-optimized operation of the internal combustion engine at the best point.
Combinations of a serial-hybrid drive with a parallel-hybrid drive are known. For example, DE 10 2007 002 734 A1 shows a combined drive train that uses a planetary gear mechanism to couple the torques of the internal combustion engine, the two electric machines and the transmission.
The object of the invention is to provide a drive train that is of simple design and can be used universally, as a combination of a serial-hybrid with a parallel-hybrid. The object of the invention also is to provide a method for operating a corresponding drive train.